Two-stroke engine of the opposed-piston type



Aug. 7, 1928.

1 380,01 7 G. FORNACA TWO-STROKE ENGINEOF THE OPPOSED PIS-TON TYPE II M Filed NOV. 10, 1926 i Fig.2

Patented Aug. 7, 1928.

' 'GUIIDO nonnaca, or 'rUnr'N, I'rALY.

FFPCE.

TWO-STROKE ENGTNE OF THE OPPOSED-IISTON TYPE.

a lication filed November 10, 1926, Serial No. 147,516, and in Italy November 17, 1925.

This invention relates to that type of two stroke internal combustion engine in which two pistons work in each cylinder, said pis-v tons moving in opposite directions and being connected, by means of connecting rods, to two separate crank shafts; its object is to provide an improved engine of this type,

more especially for aircraft, having its parts compactly arranged.

Accordingly, my invention consists of an engine of this type, characterized in that one end of the engine is provided with a casing in which is journalled the driven or propeller shaft, whereas its other end is pro-' videdwith a superfeed compressor, said casing and said compressor constituting extensions of the cylinder group.

Preferably, the driven .shaft has fixed thereon a toothed wheel in mesh with two pinions secured one on each of the crank shafts.

The compressor occupies the space between the magneto, oil pump, etc., and the body thereof constitutes a connecting means between the upper and-the lower crank cases of the engine. a

One. constructional form of my improved engine is illustrated on the accompanying drawing, V

Fig. 1 is a rear elevation of the engine. Fig. 2 is a side view, partly in section, on the line A-B of Fig. 1.

Fig. 3 is a section in the plane represented by the line C-D of Fig. 2.

Referring to the drawings, lower crank case of the engine on which are mounted the cylinders 3 whichare open at their ends and provided with admission openings 4, discharge openings 5 and sockets "6 for the sparking plugs. Upon the cylinders 3 is secured the upper crank case. 1' similar to the crank. case 1. Said crank cases are provided with an extension casing 2. Journalled in bearings in the crank cases, 1, 1' are the two crankshafts'7, 7' to 1 denotes the.

Y which the opposed pistons 9 in each cylinder 3 are connected through connecting rods 8.

Each crank shaft is provided, at one of its ends, with a pinion 10 in mesh with a reducing gear wheel 11 secured on the driven or propeller shaft 12 that is journalled-in the casing formed by "the extension 2'.

The other ends of the crank shafts carry gear wheels 13 in mesh with gear wheels 16 on the vertical shaft 14 of a superfeed compressor 15 of the rotary type, said compressor forming an extension of the cylinder group. The gear wheel 13 of the shaft 7 also operates, through apinion 17 and a reducifig gear 18, the water pump 19 and the oil pump (not shown),

The shaft 7 is provided with a pinion 20 I through which it operates the ignition magnetos 21.

Pipes 22 convey the compressed air from the compressor casing 15 to the carburettors 23. A

What I claim is:

In aninternal combustion engine with op positely arranged pistons, the combination of two end casings forming chambers, a series of cylinders containing the pistons arranged parallel to and interposed between the end casings, crank casings at both ends of the cylinders extending over and clos;

ing both chambers, crank shafts arranged in the crank casings and extending into both chambers so that their,

chambers, compressor rotors for generating axes lie parallel to those of the cylinders,

bevel gears operatively connecting .both crank shafts with-one of said rotors, adriven shaft journaled in the other chamber parallel to the crank shafts, and reducing gears in the last named chamber operatively con-' necting the driven and crank shaftsy In testimony that I claim the foregoing as my invention I have signed my name.

GUIDO FORNACA. 

